1. Field of the Invention
This invention relates to a structure floating on a body of water. More particularly, the invention relates to a floating structure from which drilling or production operations are carried out. In its more specific aspects, the invention concerns a floating structure having buoyancy means for supporting the structure and anchored to the ocean floor by parallel elongated members.
2. Setting of the Invention
In recent years there has been considerable attention attracted to the drilling and production of wells located in water. Wells may be drilled in the ocean floor from either fixed platforms in relatively shallow water or from floating structures or vessels in deeper water. The most common means of anchoring fixed platforms includes the driving or otherwise anchoring of long piles in the ocean floor. Such piles extend above the surface of the water and support a platform attached to the top of the piles. This works fairly well in shallow water, but as the water gets deeper, the problem of design and accompanying cost becomes prohibitive. In deeper water it is common practice to drill from a floating structure.
In recent years there has been attention directed toward the many different kinds of floating structures from which underwater wells can be drilled. One such drilling structure is referred to as the "vertically moored platform" and is described in U.S. Pat. No. 3,648,638, issued Mar. 14, 1972, Kenneth A. Blenkarn, inventor. In the vertically moored platform a structure is supported above the surface of the water by buoyant members. The buoyant members are connected to anchors in the floor by the body of water by long, elongated leg members which are parallel. There are no other anchoring means for the vertically moored platform.